Movable storage unit system

Abstract

A movable storage unit system comprising a plurality of individually driven storage units at least some of which are movable toward and away from one another into contact with one another to define an access space between a pair of the units. A logic control circuit is provided on each unit and a limit sensor is provided on each movable unit including a sensor circuit for creating a signal in response to contact of a pair of storage units. A safety sensor is also provided on each unit and includes a safety sensor control circuit for creating a signal upon engagement of the safety sensor and an object or person in the path of the unit. A pair of reset controls is provided on each unit including a reset control circuit for creating a logic signal when actuated, and a run control is provided on each unit for creating a logic signal when actuated. The storage units are electrically connected such that a logic signal from the run control directs a run signal to a next adjacent unit. Each logic module includes a pair of reset transmit circuits for producing reset output signals, the reset transmit circuits of the logic modules being electrically interconnected. Each logic module includes a command inhibit circuit for receiving a run signal and electrically connected to receive signals from the reset control circuits, safety control circuit, and limit control circuit of its respective storage unit to inhibit the transmittal of the run signal. Each logic module includes a pair of move transmit circuits for producing move signals, the move transmit circuits of adjacent storage units being interconnected. Each logic module includes a move steering logic circuit for producing move command signals, the move command signal actuates a drive unit of a respective storage unit in one direction or the other.

I claim: 
     
       1. In a movable storage unit system, the combination comprising a plurality of storage units at least some of which are movable toward and away from one another into and out of contact with one another to define an access space between a pair of the units,   means on each movable unit for driving said unit in two directions,   a logic control circuit on each unit,   a pair of reset controls on each unit including a reset control circuit for creating a logic signal when actuated,   a run control on each unit for creating a logic signal when actuated at a storage unit where an access space is desired,   said storage units being electrically connected such that a logic signal from said run control on the storage unit which is to move where an access space is desired directs a run signal to a next adjacent unit to cause said units to be driven successively away from said desired access space,   said run signal being inhibited by said reset control circuit unless the reset controls on the storage units on both sides of an open access space are actuated.   
     
     
       2. The combination set forth in claim 1 including time delay means operable to deactivate said logic signal from said reset controls after a predetermined time interval such that said reset controls at said access space must again be actuated. 
     
     
       3. The combination set forth in claim 1 including reset controls and a run control on both ends of each said storage unit such that the movement of the storage units can be initiated from either end. 
     
     
       4. The combination set forth in claim 1 wherein said run control to be actuated for producing motion of the storage units is always in the same orientation to the operator. 
     
     
       5. The combination set forth in claim 1 including means interlocking said control circuits such that run signals can only occur for movement in one direction at any given time and cannot occur for movement in both directions simultaneously. 
     
     
       6. The combination set forth in claim 1 including a safety sensor on each unit including a safety sensor control circuit for creating a signal upon engagement of said safety sensor and an object or person in the path of the unit, said safety sensor control circuit signal being operable to deactivate the logic module and deactivate said driving means.   
     
     
       7. The combination set forth in claim 1 wherein each said logic module includes a pair of reset transmit circuits for producing reset output signals, means electrically interconnecting reset transmit circuits of all said logic modules.   
     
     
       8. The combination set forth in claim 1 including limit sensors on each unit operable to inhibit a run signal to a successive unit until the preceding unit has moved away. 
     
     
       9. The combination set forth in claim 7 wherein each said logic module includes a command inhibit circuit for receiving a run signal and electrically connected to receive signals from said reset control circuits of its respective storage unit to inhibit the transmittal of the run signal, said logic module including a pair of move transmit circuits for producing move signals,   means interconnecting the move transmit circuits of adjacent storage units,   each said logic module including a move steering logic circuit for producing move command signals,   and means responsive to said move command signals for actuating the drive unit of the respective storage unit in one direction or the other.   
     
     
       10. The combination set forth in claim 9 wherein each said command inhibit circuit of each logic module includes a time delay circuit operable to prevent transmittal of a run signal.